Furnace charging apparatus



April 3o, 1963 A. c; BUE-sm@ am.

- 3,087,633 FURNACE CHARGING APPARATUS i Filed Jan. 16, 1961 J mi 4 Sheets-Sheet 1 INV EN TORS NNI April 30, 1963 A. c. 'BUEsING ETAL .FURNAQE cHAmNcAPPAmTus 4 Sheets-Sheet 2 Filed Jan. 16. 1961 I NV EN TORS men/ae c. wes/M6;

April 30, 1953 A. c. BuEslNG ETAL 3,087,633

FURNACE CHARGING APPARATUS 4 Sheets-Sheet 3 Filed Jan. 16, 1961 www April 30 1963 A. c. BuEsxNG ETAL 3,087,633

FURNACE CHARGING APPARATUS Filed Jan. 16, 1961 4 Sheets-Sheet 4 IN VEN TORS ,4er/,faz c. afs/M6, /fAA/c/.s 7: 1.44/56@ Riem/hm, #MMX/(m United States Patent O 3,087,633 FURNACE CHARGING APPARATUS Arthur C. Buesing, North Olmsted, and Francis T. Kaiser,

Fairview Park, Ohio, assignors to Brown Fintube Company, Elyria, Ohio, a corporation of Ohio Filed Jan. 16, 1961, Ser. No. 82,884 7 Claims. (Cl. 214-2) This invention relates to apparatus for charging metal melting furnaces, and more particularly to apparatus embodying vibratory means for charging sha-ft furnaces.

Although the invention may be employed to advantage in various services, it will be described in connection with the charging of foundry cupolas, since it provides exceptional advangtages in such use.

In the changing of such cupolas, several important conditions must be satisfied for best and most economical oper-ation. The charge should consist of an accurately determined weight of proper charging ingredients. In usual ferrous foundry practices, the metallic constituents of the charge are deposited by an electromagnet into a `chargin-g conveyance, and other constituents such as limestone and coke of which considerably smaller quantities are used, are either hand loaded or loaded by mechanical means into the charging conveyance. The conventional charging conveyance usually employed lis a bucket having a bottom which can be opened to drop the charge into the furnace after the bucket has been moved into the furnace above the material being melted in the furnace. However, it is difficult to load the bucket with the charge constituents since its relatively small top opening affords only a small target for the magnet used in loading the metal constituents, or for manual or :automat-ic loading the other charge constituents. Moreover, the relatively great depth of the bucket makes it very difficult or impossible to intermix the charge constituents in the bucket sufficiently to provide the desired uniformity of composition of material charged -into the cupola, .and for the oper- -ator to trim lthe charge or remove excessive charge constituents inadvertently deposited in the bucket.

Bach succeeding charge should be deposited on the material in the cupola ras nearly as possible in a layer of uniform composition to obtain efficient melting and a homogeneous, high quality metal product. Preferably, at least the limestone and coke should .be deposited in the center of the furnace cross section. However, the conventional bucket charger or similar charging means heretofore used drops each charge into the furnace in .the form of a single compact mass or slug of heterogeneous composition, and in such 4a non-uniform manner that the lighter constituents of the charge such as limestone and coke are deposited away from the center of the furnace cross section, while the heavier constituents such as the metallic materials are `deposited centrally of the furnace cross section. Limestone thus deposited near the furnace wall causes excessive .and uneven burnout of the refractory furnace lining. Depositing of the coke near the furnace wall and the metallic charge constituents at the central portion of the `furnace cross section causes the blast air to channel through the .coke near the furnace wall without penetrating substantially into the body of charge material in the furnace. This results in slow gas reaction time, increased oxidation of the metal, and lower metal temperatures.

Moreover, charge material dropped into the furnace in a single large compact mass or slug strikes with high impact the charge material already in the furnace and the furnace lining. This crushes lthe coke and causes undesir-able coke breakage, compacts .the charge material in the furnace and causes poor blast air distribution, and causes considerable wear and abrasion lof .the furnace 1ining, often necessitating its replacement particularly in the ice vicinity `of the charging doorway. In order to protect the cupola furnace in the vicinity of the charging doorway from the high impacts ofthe charged material, it has been found necessary to provide elaborate and costly protective means such as sills, liner blocks and bumper blocks of cast iron or steel at this portion of the furnace. These parts require frequent replacement, as they deteriorate from the abrasion of the charging material and from the heat of the furnace. Moreover, these deteriorating influences -often distort the furnace shell itself sufficiently to require its replacement.

The bottom-opening bucket or similar conveyance usually employed `as a charging conveyance itself often introduces operating difficulties and requires considerable maintenance to keep it operable. The mechanism for opening and closing the bottom of the bucket is necessarily quite complicated and liable to deterioration or malfunctioning from clogging and yabrasion of the charging materials and from the heat to which the bucket is subjected.

Such repairs and maintenance work on furnace linings, doorways, sills, and bumpers, buckets, yand other parts of the .aparatus not only are costly but also result in loss of considerable production time.

Furthermore, a cupola furnace charged by a bottomopening bucket or similar conveyance must have a re1- atiyely large charging doorway to permit .the relatively deep bucket or conveyance and its `supporting means to enter the furnace. Since it is not feasible to close land open the doorway between each charging step, the doorway usually is not provided with closure doors. The constantly open large doorway results in a considerable heat loss and a corresponding increase in cost of operation. The large quantities of radiant heat escaping through the open doorway `also tend to deteriorate 4the cupola shell around and above the doorway opening, endanger nearby mechanisms and building structure, and cause `other safety hazards. The large doorway also necessitates expensive reinforcement of the furnace shell.

F or convenience rand efliciency in loading, the top opening of the charging convey-ance should be at or only slightly above ground level in the loading station. Since the charge-weighing means must be located below the charging conveyance, a pit is usually required. When a bucket or similar conventional charging conveyance of consider-able depth i-s employed, the pit must be quite deep. This not only adds to the cost of installation, but also often introduces flooding problems if the plant is loc-ated in an -area having a high water table.

A slow charging cycle results from the above-described difficulties in loading a conventional bottom-opening bucket or similar conveyance and the time required to position the bucket in the cupola, open it and close it. Consequently, in modern high production foundry practices, it is necessary that the bucket be quite large in order to prov-ide the necessary high charging rate. The large bucket accentuates the above-indicated difficulties. It requires a Ilarger charging doorway, with resulting greater heat loss and deterioration of the cupola shell. It results in the dropping of a larger compact mass of charge material into the furnace, with attendant increased difficulties due to high impacts of the dropped charge materials, increased abrasion and wear of the furnace lining, and increased coke breakage. The composition of the burden in the furnace also is less uniform when large charges are supplied than when smaller increments are provided.

These problems are overcome and other important advantages are provided by the apparatus of the present invention. Such apparatus comprises a vibratory charger conveyance. Such conveyance is supported on suitable means such as a track which permits it to be moved from a loading station where, while not vibrating, it is loaded with the proper weights of proper change constituents, to a discharge station adjacent the cupola furnace in which position its discharge end projects into the furnace and in which it is vibrated to discharge the charge constituents into the furnace. Preferably, the vibratory conveyance is located so its charge supporting bottom is at all times at a substantially horizontal position even if it moves in a path from a lower loading station to an upper discharge station.

Since the vibratory charger conveyance preferably comprises an elongated relatively wide and shallow vibrating trough having an open top and discharge end, it provides a large target for rapid loading, facilitating loading of ferrous metallic charge constituents by a magnetic loader, as well as loading of other charge constituents by hand or automatic means. Furthermore, the shape of the charger trough is such that it readily makes possible thorough mixing of the charge materials and removal of any excess constituent which might have been placed in the trough. For these reasons the apparatus of the invention promotes rapid loading of a charge of proper weight and composition into the vibratory conveyance.

This proper weight and composition of charge, and the vibrating action of the conveyance causes the charge material to discharge quite gradually into the furnace in the form of a stream and to be deposited in successive layers of highly uniform composition. A larger proportion than heretofore possible of limestone, coke and other light constituents of the charge is deposited in the central area of the furnace cross section. Concurrently, more of the heavier metallic constituents are deposited away from the center of the furnace cross section than is possible with conventional bucket-type chargers. The resulting highly uniform distribution of charge constituents prevents excessive and uneven lining burnout from the limestone, and provides a highly uniform distribution of blast air flow through the body of charge material in the furnace due to equalization of air ow resistance in the body. These factors result in considerably faster and more uniform gas reactions, substantially less oxidation of the metal, and higher melting temperatures; consequently, better quality of metal results at a higher rate of production. Since the charge drops in stream form into the central portion of the furnace, the charge material does not strike against the sides of the furnace, thus eliminating wear or abrasion on the furnace lining from this cause. This makes it unnecessary to provide the elaborate, expensive and troublesome protective sills, liner blocks or bumper blocks heretofore employed in the vicinity of the furnace doorway.

The apparatus of the invention is also free of tendencies toward deterioration, jamming or clogging characteristic of `conventional bottom-opening buckets, since the charge material is discharged over the edge of the vibratory conveyance. Therefore, after the charge material has been discharged and the conveyance returns to the loading station, it is immediately ready for reloading. Because of its simplicity of construction and operation, little maintenance is required to keep the apparatus of the invention in operating condition. Not only is the cost of maintenance substantially lowered, but shut-down times for maintenance or repair are greatly reduced.

A much lower and small charging doorway may be employed in the furnace with the apparatus of the present invention than is possible with other types of prior apparatus such as those employing buckets. This arises because only the discharge end of the vibratory trough of the charging conveyance need project into the furnace. The smaller, lower furnace doorway makes possible a great reduction in heat loss, and reduces the quantity of escaping heat so that deterioration of the cupola shell and safety hazards are eliminated.

Since the vibratory trough of the conveyance can be made very shallow, the overall height of the conveyance can be reduced so that the loading station requires a considerably shallower pit than necessary in conventional practice, with savings in installation costs and avoidance of other difliculties.

It is an object of the invention to provide furnace charging apparatus embodying a vibratory charging conveyance which makes possible the above advantages, which is simple and dependable in operation, and which may be installed at moderate cost.

Other objects and advantages of the invention will be apparent from the following description of a preferred form, reference being made to the accompanying drawings in which:

FIGURE l is a side elevation of cupola charging apparatus embodying the invention, with the vibratory -charging `conveyance in its loading station at the lower end of the apparatus, the pit in which the lower end is installed being shown in sections;

FIGURE 2 is a plan of the apparatus of FIGURE 1;

FIGURE 3 shows the lower portion of the apparatus of FIGURE 1, to a larger scale;

FIGURE 4 is a plan of the portion of the apparatus of FIGURE 3, but to the same scale;

FIGURE 5 is a sectional elevation along line 5-5 of FIGURE 1, and to the same scale as FIGURES 3 and 4;

FIGURE 6y is a plan of the skip car member forming part of the vibratory charging conveyance, `but to a scale slightly larger than that of FIGURES 3 and 4;

FIGURE 7 is a sectional elevation of the skip car member of FIGURE 5, along line 7 7 of FIGURE 6;

FIGURE 8 is a portion of the skip car member along line 8 8 of FIGURE 6 showing how the wheels thereof ride on the rails;

FIGURE 9 is a perspective elevation of the frame member which is carried by the skip car member; and

FIGURE l0 is a perspective elevation of the vibratory member, including the trough portion adapted to carry the charge material, which is adapted to be resiliently supported by the frame member.

The illustrated apparatus comprises a vibratory charging conveyance 1 for the charge material, which conveyance is adapted to travel on a track generally indicated by :reference numeral 2 from a loading station generally indicated by numeral 3 at which the conveyance is loaded with charge material, to a discharge station indicated generally by reference numeral 4 at which charge material is discharged from the conveyance 1 into a cupola furnace 5 through its doorway 6. The furnace is supported by floor 7 which, at a location spaced from the cupola, has formed in it a pit 8 containing a weighing means 9 which weighs the charge material loaded into conveyance 1 when it is at its loading station 3.

The track 2 comprises two spaced parallel rails 11 inclined with the lower end of each disposed in the pit 8 and .the upper end of each located adjacent the doorway 6 of the furnace 5. Each of the rails 11 is of I-beam cross section. Facing surfaces of the flanges on the inside of the rails are provided with wear strips 12 and 13 (FIG- URE 8) where they are contacted by the wheels of the conveyance 1. The rails 11 are rigidly supported relatively to each other and to the floor and cupola S by suitable framing structure 14, 15 and 15.

The conveyance 1 comprises a skip car member 21 supported by and adapted to travel on the rails 11 of the track 2; a frame member 22 adapted to be carried by the skip car member 21 while the car member 21 is traveling on the rails 11 and while it is stationary in the discharge station 4, and also adapted to be carried free of member 21 by the weighing means 9 when the conveyance -1 is located in the loading station; and a vibratory member 23 resiliently carried by frame 22. As shown in FIG- URES 6-8, the skip car member 21 comprises a frame structure having at its ends non-rotatable transversely extending parallel tubular axle members 24 and 25 rigidly fixed to two spaced, parallel longitudinally extending members 26. Each axle member carries a pair of rotatable lianged wheels 27 adapted 'to travel on the lower wear strips 12 of the side rails 11 of the track 2. The front axle member 24 on its front surface rigidly carries two guide lugs 28 which aid in locating the frame member 22 on skip car member 21. The rear axle member 25 rigidly carries a pair of web members 29 which are also fixed to the longitudinal members 26; the outer sides of these web members act as guiding lugs for the frame member 22, and each web member 29 also rotatably carries the sheave 31. A cable 32, one end of which is fixed to the upper end of one of the side rails 11, passes along such rail, around such sheaves 31, and along the other rail to its upper portion from which it passes over sheave 33 to an electrically driven hoisting unit 35. When the hoisting unit rotates in the direction to wind the cable, the skip car member travels upwardly along the track 2 and when the hoisting unit unwinds the cable the skip car travels downwardly. By proper control of the lhoisting unit the conveyance 1 thus can be readily moved from its loading station 3 to its discharge station 4 and vice versa.

The frame member 22, as is apparent from FIGURE 9, comprises longitudinally extending side members 36 rigidly iixed to two transversely extending end members 37 and 38. At each corner of the resulting structure there is fixed an upwardly extending guard member 39. The frame member 22 also includes two upwardly extending side plates 41 each having a rearwardly opening slot 42 fixed to the side members 36 and the forward guard .members 39, and two downwardly extending side plates 43, iixed to the bottom of the side members 36, and having rearwardly opening slots 44. As is shown in FIG- URE 3 these slots are so located and shaped that when the skip car member is out of the loading station 3, the ends of the front axle members 24 of the skip car member 21 lit into the slots 42 of the front side plates 41 and the ends of the rear axle members 25 lit into the slots 44 of the lower rear side plates 43 of the frame member 22; and when the conveyance 1 is in the loading station 3, and the frame member 22 is wholly supported by scale means 9 as will be described later, the axle members 24 and 25 of the skip car member being located rearwardly of the end slots 42 and 44 of the side plates 41 and 43 sufficiently so that they do not contact the slots and the skip car member is not weighed. The frame member 22 also includes two spring supports 45 located near the front corners of frame member 22, and four spring supports 46 located on the rear end member 38 of frame member 22. Each of these spring supports carries a lower end of a compression type coil spring 47 (see FIGURES 3 and 4), the spring supports being formed as shown to prevent lateral displacement of the springs relatively to the frame member 22. The upper ends of the springs resiliently support the vibratory member 23.

In the illustrated embodiment, as shown in FIGURES 3, 4, 5 and l0, the vibratory member 23 comprises a trough portion 51 to the bottom of which is fixed power means, contained in housing 52, which imparts a vibratory motion longitudinally of the trough with little if any transverse component of motion. The illustrated trough portion which is of relatively shallow conguration comprises -a solid bottom Wall 53, two outwardly inclined upright side walls 54 iixed to the bottom wall, a rear wall 55 and an open or unobstructed discharge end 56 at its front, the top of the trough being open. Preferably, the top of the trough portion is provided with an outwardly extending skirt portion 57 and an upwardly extending wall 58; the wall aids in loading of the trough by minimizing scattering of the charge material while the skirt portion 57 aids in protecting the vibratory mechanism and the scale mechanism from materials which might inadvertently be scattered. Near its front portion the vibratory member 23 is provided with projecting spring seats 59, and at its rear portion is provided with spring seats 61, all of which engage the upper ends of the springs 47 in such manner that the lateral movement relatively to the springs and to the seats is prevented.

The power means for the vibratory member 23, enclosed in housing 52 and not shown, is of a commercially available type comprising synchronized unbalanced shafts rotating in opposite directions about parallel axes extending transversely of the trough portion of the vibratory member, the shafts being rotated by suitable electric motors, not shown. When the motors rotate while the conveyance 1 is in the discharge station adjacent the cupola furnace, the power means develops a short stroke Vibration on the order of 1/2" to 1 in amplitude at a lfrequency of several hundred cycles per minute. If, as in the illustrated embodiment, the apparatus is designed so that the bottom of the trough portion 51 is substantially horizontal when the conveyance is in the discharge position as well as in all other locations, such vibration causes the charge material to move forward toward the discharge end of the trough portion and be discharged therefrom in the form of a stream of charge material.

As was indicated above, when the conveyance 1 is in the loading station 3, the portion of the conveyance made up of the vibratory member 23 and the frame 22 is supported bythe weighing means 9, free of the skip car memfber 21. The weighing means 9, as shown in FIGURES 3 and 4, is a widely used commercially available type comprising spaced pedestals fixed to the lioor of the pit 8. Each pair of pedestals 65 supports, through suitable lfulcrum means 66, a lever member 67; the inward facing ends of lever member 67 are connected to an intermediate lever member 68 pivotally mounted on a pedestal 69 fixed to the iioor of the pit. Intermediate lever 68 is connected by suitable linkage means to an indicating scale 70 (FIGURE Z) adapted to indicate visually the weight, record the weight, or both indicate and record the weight. Each lever member 67 supports a pair of loadcarrying members 71 through suitable fulcrum means 72. Four load-carrying members 71 are shown as rigidly xed to and support -a scale frame 7.3;this frame, which is a rigid structure, comprises two transversely extending members 74 and 75 and two longitudinally extending members 76. The transverse members 74 and 75 are rigidly fixed to pedestals 77 which are bolted to the load-carrying members 71 of the weighing means.

The illustrated apparatus, as is preferably, embodies means for guiding and locating the conveyance frame member 22 onto the scale frame 73 when the conveyance 41`moves into the loading station 3. Such means comprises vertically extending lugs 81 fixed to the rear trans- `verse member of scale frame 73 in such position as` to locate the conveyance frame 22 transversely and to labut against horizontally extending lugs 82 iixed to the outer surfaces of the rear portions of the side members 36 of frame member 22, to limit rearward movement of conveyance member 22 relatively to scale frame 73. The locating means also includes two inclined -shoe portions 83 xed to the front transverse member 74 of scale frame 73 and adapted to it two inclined surfaces 84 on the front portions of the side members 36 of conveyance frame member 22, the angle of inclination being such that these surfaces are parallel to the rail 11 Aand hence to the direction of travel of the conveyance frame member 22. Furthermore, each shoe member 83 is provided with an upwardly extending lug 85 adapted to bear against the adjacent side of the conveyance frame member 22 to locate the front portion of said iframe transversely. Consequently, when the conveyance 1 moves downwardly into the loading station, these parts of the locating means accurately locate the portion of the conveyance comprising the frame member 22 and the vibratory member 23 on the scale frame 73 in position for accurate weighing of charge material deposited in the trough member 51 of the l conveyance, while the skip car member 21 is carried wholly by the rails 11.

In order to guide the scale frame vertically during the weighing operation, and to prevent substantial longitudinal or transverse motion of the scale frame during placement of the conveyance frame member 22 on or removal of it from the scale frame, the outer end of each transverse member 74 and 75 of the scale frame is provided with both longitudinally and transversely extending adjustable guide bolts S7 and 88 adapted to bear against vertically extending angle members 89 fixed in the pit 8.

The conveyance 1 also includes a member 91 fixed to the frame member 22 for supporting the required number, three in the illustrated embodiment, of electrical conductor shoes 92, which are electrically connected to the power means 52 of the vibratory member 23. These shoes are adapted to contact `and make electrical connection with the corresponding number of -suitable electrical conductor members 93 supported in insulated relation at the upper end of the track 2 in such manner that when the conveyance is located in the discharge station 4 with its discharge end in proper position in the furnace cupola, electrical power can be supplied unto the power means for the vibratory member 23. Circuit means can be arranged so that the vibratory action is automatically started when the conveyance 1 moves into the discharge station, or the power may be separately connected either manually or by separate automatic means.

Preferably, the upper portion of the track 2 adjacent the furnace 5 is provided with limit switch means 94 on at least one of the rails 11, adapted to be engaged by a suitable lug 95 fixed to the skip car member 21 so that power to the hoisting means 35 is disconnected and the hoisting means is halted to stop the conveyance 1 in the proper position in the discharge station 4 adjacent the furnace. Similarly, a limit switch 96 is located on the same rail of the track 2 near its lower end to be contacted by lug 95 to disconnect power from the hoisting means to halt the conveyance 1 when it reaches the proper positron in the loading station 3, with its frame member 22'resting on scale frame 73; in this case the limit switch 1s arranged so that the skip car member 21 travels downwardly on the rails a short distance beyond the pomt where the frame member 22 halts, so that the ends of the axle members 24 and 25 of the skip car member 21 move in slots 42 and 44 of the frame member 22 to positions where they cannot contact the sides of the slots as the frame member 22 moves downwardly during loading and weighing. Y i

Preferably, at the top of pit 8 the loading station 3 1ncludes a platform 97 which lits closely adjacent the sldes and the rear of the trough member 51 when the conveyance 1 is in the loading station, the the top of which is located at or slightly below the level of the top and the trough member 51. In the illustrated embodiment the scale 70' is located on or adjacent the platform. The platform facilitates loading, particularly if one or more charge constituents are hand loaded into the trough portion 51.

The operation of the illustrated apparatus is as follows, assuming that initially the conveyance 1 is in the discharge station 4, and that its trough portion 51 is empty and not vibrating. The hoisting unit 35 is then energized to lengthen the cable 32 and permit the conveyance 1 to move downwardly by gravity into the loading station 3, under control of the cable 32 passing around the sheaves 31 on the skip car member 21 and the sheaves 33 and 34 at the upper end of track 2.

As the conveyance 1 moves into the loading station, the bottom of the conveyance frame member 22 seats on the top of the scale frame 73, being located longitudinally by lugs 82 at the rear and the inclined surfaces 84 at the front of conveyance frame member 22, respectively bearing against lugs v81 at the rear and the inclined surfaces of the shoe members 83 at the front of the scale frame 73. As it seats, the conveyance frame member 22 is located transversely by contact of its sides with the lugs 81 and 85 on the scale frame 73. The scale frame itself is located longitudinally and transversely by the guide bolts 87 and 88 fixed to the corners of the scale frame 73 and cooperating with the vertical guide members 89 fixed in the pit 8.

As the conveyance frame member 22 thus seats on the scale frame, the skip car member 21 continues to move downwardly along the track 2 and away from the furnace 5 for a short distance, until it is halted by contact of its lug with limit switch 96 on the track 2, thus disconnecting power from the hoisting unit 35 and stopping it and halting unwinding of the cable 32. The skip car member 21 thus moves suiciently to disengage the ends of the skip car axle members 24 and 25 from the slots 42 and 44 in the plate members 41 and 43 forming parts of the conveyance frame member 22, and to provide sufficient space between these axle members and the slots to permit the conveyance frame member 22 to be wholly supported by the scale frame 73 at all times during the loading and weighing operation; the sides of the slots are tapered to facilitate this. Therefore, no part of the weight of the skip car member is at any time supported by the weighing means.

The trough member 51 forming part of the vibratory member 23 of the conveyance is then loaded either manually or mechanically with the various constituents of the charge material, the large top opening of the trough member 51 facilitating either type of loading. More particularly, this large top opening facilitates the loading of ferrous charge constituents by magnetic means. Moreover, this large top opening as Well as the shallow conliguration of the trough member S1 facilitate substantial intermixing of the charge constituents in the trough. The weight of each constituent and the total weight of the charge material loaded are readily and rapidly indicated by the scale indicators 70; if too much of any charge constituent is inadvertently added, the shallow configuration and the large top opening of the trough member 51 facilitate removal of the excess.

After the conveyance 1 has been properly loaded with the proper amounts of the charge constituents, the hoisting unit '35 is energized to wind the cable 32 and cause the skip car member 21 to move upwardly along the track 2 toward the furnace 5. Initially the car member 21 moves until the ends of its axle members 24 and 25 engage the closed ends of the slots 42 and 44 of the conveyance frame 22, thus properly locating frame member 22 and the skip car member 21 longitudinally relatively to each other; these members 21 and 22 are properly located transversely relatively to each other by contact of the outer edges of the lugs 28 on front axle member 24 of skip car member 21 with the inner sides of the plate mernbers 41 at the front end of the conveyance frame member 22, and by contact of the outer edges of web members 29 xed to rear axle member 25 of the skip car member with the inner sides of the plates 43 at the rear end of the conveyance frame member 22.

This seating of the conveyance frame member 22 on the skip car member 21 occurs rapidly and infallibly with no interruption of the movement of the skip car member. As the skip car member 21 travels upwardly on the track 2 toward the furnace 5, it carries with it the conveyance frame member 22 supporting the loaded vibratory member 2'3, the movement out of the loading station being facilitated by the above-described inclination of the surfaces `of the locating shoe members 83 and cooperating surfaces on the conveyance frame member. The thus completed conveyance 1 carrying the load of charge material is drawn upwardly along the track 2 by the cable 32 until it moves into the discharge station 4 adjacent the furnace 5. The lug 95 on the skip car member 21 then contacts and opens the limit switch means 94 at the upper end of the track 2, thus de-energizing and stopping hoisting unit 35 and halting movement of cable 32 and of skip car member 21. The limit switch means 94 and the other parts are so located and arranged so that the conveyance 1 stops with the discharge end of its trough member 51 projecting in the proper position through the doorway 6 of the furnace 5. This position is such that substantially all charge material passing from the discharge end of the trough member 51 drops into the central area of the furnace cross section. When the conveyance 1 moves into such discharge station 4, the conductor shoes 92 carried by the skip car member 21 make electrical Contact with the conductor members 93 fixed to the upper end of the track 2.

By manually or automatically controlled means, electrical power is then supplied through such shoes 92 and conductors 93 to the power means S2 of the conveyance zl; the power means imparts a predetermined type of vibratory movement to the member 23, which movement causes the charge material in the trough member 51 to travel lengthwise of the trough toward its discharge end from which it drops in a stream-like mass into the central area of the cross section of furnace 5. Preferably, the vibratory movement has a small amplitude no greater than about one inch, and has a frequency of several hundred cycles per minute in a direction longitudinally of the trough member 51, with substantially no transverse component of vibratory movement. The vibratory movement also tends to mix the charge constituents in the trough member 51 as they travel toward the discharge end of the trough member. For this reason, and because of the stream-like character of the discharge and because of the premixing possible during the loading operation, the charge material may be discharged into the furnace with a high degree of uniformity. `Since the material is discharged into the central portion of the furnace cross section, little if any can strike the furnace lining in the vicinity of the doorway or elsewhere, so that abrasion or wear due to this cause is substantially completely eliminated. Furthermore, since discharge end of the vibratory member 23 of the conveyance 1 is precisely inserted into and withdrawn from the furnace with no possibilities of swinging, swaying or deflection, and since the discharge movement is a small amplitude vibratory movement longitudinally of the direction of insertion, there is no possibility that any part of the conveyance 1 can strike the furnace at the doorway 6 or elsewhere, so that expensive and elaborate protective metal sills, linings or bumpers are not required at these points. The doorway itself may be of much smaller area than in conventional practice, since it is only necessary to provide space for the insertion and withdrawal of the discharge end of the shallow trough member 51; therefore, heat losses from the furnace are greatly reduced, as are possibilities of deterioration or damage to the furnace in the vicinity of the doorway due to large amounts of escaping heat. Furthermore, the cycle of loading and discharge operations can be rapid and extremely efficient, which reduces production costs.

According to an actual example of operations of an apparatus embodying the invention similar to that illustrated employed in connection with a foundry cupola for melting ferrous metals, the conveyance 1 had a trough member 23 approximately eight feet long, three feet wide, and 15" deep; it was loaded with a charge consisting of 2,000 lbs. of ferrous scrap metal, 250 lbs. of coke and 60 lbs. of limestone. The conveyance 1 was moved at a speed of 60 feet per minute for a distance of 48 feet from the loading station to the discharge station; the charge was unloaded by vibration of the vibratory member at 921 cycles per minute through a stroke of 11/32 inch amplitude in the direction longitudinally of the vibratory member for about l seconds. After unloading, the conveyance -1 was returned empty to the loading station. Each complete cycle required only six minutes and the apparatus operated continuously and efficiently on every cycle.

It is apparent that the present invention provides furnace charging equipment Awhich satisfies all of the desirable requirements while eliminating the shortcomings of prior apparatus. The apparatus of the invention is simple and rugged in construction and can operate for long periods with little maintenance.

While the invention has been described herein in a preferred embodiment, those skilled in the art will appreciate that it may be adapted to other purposes than that disclosed and that various changes and modifications can be made in the preferred form described herein without departing from the spirit and scope of the invention.

We claim:

l. Apparatus for charging a furnace for melting material, comprising a loading station spaced from the furnace; track means extending between said loading station and said furnace; weighing means in said loading station; and a conveyance comprising a skip car member supported on said track means While said skip car member is in said loading station and while traveling on said track means between said loading station and an unloading position adjacent said furnace, a frame member having means by which said frame member is engaged and supported by said skip car member while said skip car member is traveling and while it is in said unloading position, and by which said frame member is disengaged from said skip car member to permit said frame member to be supported by said weighing means free of said skip car member` v when said skip car member and said frame member are in said loading station, a feeding trough member resiliently mounted on said frame member and having a discharge end which is positioned directly above the material being melted in said furnace when said conveyance is in said unloading position adjacent said furnace, and means for vibrating said trough member to cause material carried by said trough member to drop from its discharge end into said furnace when said conveyance is in said unloading position adjacent said furnace.

2. Apparatus for charging a furnace for melting material, comprising a loading station spaced from the furnace; track means extending between said loading station and said furnace; weighing means in said loading station; and a conveyance comprising a skip car member supported on said track means while said skip car member is in said loading station and while traveling on said track means between said loading station and an unloading position adjacent said furnace, a frame member having means by which said frame member is engaged and supported by said skip car member while said skip car member is travcling and while it is in said unloading position, and by which said frame member is disengaged from said skip car member to permit said frame member to be supported by said Weighing means free of said skip car member when said skip car member and said frame member are in said loading station, a feeding trough member resiliently mounted on said frame member and having a discharge end which is positioned directly above the material being melted in said furnace when said conveyance is in said unloading position adjacent said furnace, means for vibrating said trough member to cause material carried by said trough member to drop from its discharge end into said furnace when said conveyance is in said unloading position adjacent said furnace; means for accurately locating said conveyance on said track means in said position adjacent said furnace; and means for accurately locating said frame member on said Weighing means when said conveyance is in said loading station.

3. Apparatus for charging a furnace for melting material, comprising a loading station spaced from the furnace; track means extending between said loading station and said furnace; weighing means in said loading station; and a conveyance comprising a skip car member supported on said track means when said skip car member is in said loading station and while traveling on said track means between said loading station and an unloading position adjacent said furnace, a frame member having means by which said frame member is engaged and supported by said skip car member while said skip car member is traveling and while it is in said unloading position, and by which said frame member is disengaged from said skip car member to permit said frame member to be supported by said weighing means free of said skip car member when said skip car member and said frame member are in said loading station, a feeding trough member resiliently mounted on said frame member and having a discharge end which is positioned directly above the material being melted in said furnace when said conveyance is in said unloading position adjacent said furnace, and power means carried by said trough member for vibrating said trough member to cause material carried by said trough member to drop from its discharge end into said furnace when said conveyance is in said position adjacent said furnace.

4. Apparatus for charging a shaft furnace with charge material above the material being melted in said furnace comprising a loading station located at a position spaced from the furnace and at a lower level than the position at which material is unloaded into said furnace; track means extending between said loading station and said unloading position from which charge material may be deposited in said furnace; weighing means in said loading station; and a conveyance comprising a skip car member supported on said track means while said skip car member is in said loading station and while traveling on said track means between said loading station and said unloading position, a frame member having means by which said frame member is engaged and supported by said skip car member while said skip car member is traveling and while it is in said unloading position, and by which said frame member is disengaged from said skip car member to permit said frame member to be supported by said weighing means free of said skip car member when said skip car member and said frame member are in said loading station, a feeding trough member which is resiliently mounted on said frame member, the bottom of said trough member at all times longitudinally extending at a substantially constant angle relative to the horizontal, said trough member having a discharge end which is positioned directly over the material being melted in said furnace when said conveyance is in said unloading position, and means for vibrating said trough member longitudinally thereof to cause material carried by said trough member to drop from its discharge end into said furnace when said conveyance is in said unloading position adjacent said furnace.

5. Apparatus for charging a shaft furnace with charge material above the material being melted in said furnace comprising a loading station located at a position spaced from the furnace and at a lower level than the position at which material is unloaded into said furnace; track means extending between said loading station and said unloading positionfrom which charge material may be deposited in said furnace; weighing means in said loading station; a conveyance comprising a skip car member supported on said track means while said skip car member is in said loading station and while traveling on said track means between said loading station and said unloading position, a frame member having means by which said frame member is engaged and supported by said skip car member while said skip car member is traveling and while it is in said unloading postion, and by whch said frame member is disengaged from said skip car. member to permit said frame member to be supported by said weighing means free of said skip car member when said skip car member and said frame member are in said loading station, a feeding trough member which is resiliently mounted on said frame member, the bottom of said trough member at all times longitudinally extending at a substantially constant angle relative to the horizontal, said trough member having a discharge end which is positioned directly over the material being melted in said furnace when said conveyance is in said unloading position, and means for vibrating said trough member longitudinally thereof to cause material carried by said trough member to drop from its discharge end into said furnace when said conveyance is in said unloading position adjacent said furnace; means for accurately locating said conveyance on said track means in said position adjacent said furnace; and means for accurately locating said frame member on said weighing means when said conveyance is in said loading station.

6. Apparatus for conveying and discharging a predetermined weight of material comprising an unloading station; a loading station spaced from said unloading station; spaced generally parallel track members positioned in said loading station and upwardly inclined therein in the direction toward said unloading station; weighing means in said loading station, said weighing means including a frame located between said track members and having an upwardly facing generally horizontal supporting surface; a skip car member carrying rollers which support said skip car member on said track members while said skip car member travels and while it is stationary in said loading station, said skip car member having engaging means extending transversely of its direction of travel; means for moving said skip car member along said track members into and out of said loading station; a frame member narrower than the distance between said track members having slotted engaging means so slotted that when said skip car member moves upwardly along said track members out of said loading station said slotted engaging means are engaged by said transversely extending engaging means on said skip car member and when said skip car member travels downwardly into said loading station said transversely extending engaging means on said skip car member disengage from said slotted engaging means on said frame member and permit said frame member to rest on said frame of said weighing means free of said skip car member.

7. Apparatus for charging a furnace for melting material comprising a loading station spaced from the furnace; track means extending between said loading station and said furnace; weighing means in said loading station; and a conveyance comprising a skip car member supported on said track means while said skip car member is in said loading station and while traveling on said track means between said loading station and an unloading position adjacent said furnace, and a feeding trough member which is resiliently carried by said skip car member while said skip car member is traveling and while it is in said unloading position and which is disengaged from said skip car member and supported by said weighing means free of said skip car member when said skip car member and said trough member are in said loading station, said trough member having a discharge end which is positioned above the material being melted in the furnace when said conveyance is in said unloading position adjacent said furnace, and means for vibrating said trough member to cause material carried by said trough member to drop from its discharge end into said furnace when said conveyance is in said unloading position adjacent said furnace.

References Cited in the file of this patent UNITED STATES PATENTS 11,871,559 Reed Aug. 16, 1932 2,773,610 Mohr et al. Dec. 11, 1956 2,815,135 Kullmar Dec. 3, 1957 2,962,174 Shekels Nov. 29, 1960 

1. APPARATUS FOR CHARGING A FURNACE FOR MELTING MATERIAL, COMPRISING A LOADING STATION SPACED FROM THE FURNACE; TRACK MEANS EXTENDING BETWEEN SAID LOADING STATION AND SAID FURNACE; WEIGHING MEANS IN SAID LOADING STATION; AND A CONVEYANCE COMPRISING A SKIP CAR MEMBER SUPPORTED ON SAID TRACK MEANS WHILE SAID SKIP CAR MEMBER IS IN SAID LOADING STATION AND WHILE TRAVELING ON SAID TRACK MEANS BETWEEN SAID LOADING STATION AND AN UNLOADING POSITION ADJACENT SAID FURNACE, A FRAME MEMBER HAVING MEANS BY WHICH SAID FRAME MEMBER IS ENGAGED AND SUPPORTED BY SAID SKIP CAR MEMBER WHILE SAID SKIP CAR MEMBER IS TRAVELING AND WHILE IT IS IN SAID UNLOADING POSITION, AND BY WHICH SAID FRAME MEMBER IS DISENGAGED FROM SAID SKIP CAR MEMBER TO PERMIT SAID FRAME MEMBER TO BE SUPPORTED BY SAID WEIGHING MEANS FREE OF SAID SKIP CAR MEMBER WHEN SAID SKIP CAR MEMBER AND SAID FRAME MEMBER ARE IN SAID LOADING STATION, A FEEDING TROUGH MEMBER RESILIENTLY MOUNTED ON SAID FRAME MEMBER AND HAVING A DISCHARGE END WHICH IS POSITIONED DIRECTLY ABOVE THE MATERIAL BEING MELTED IN SAID FURNACE WHEN SAID CONVEYANCE IS IN SAID UNLOADING POSITION ADJACENT SAID FURNACE, AND MEANS FOR VIBRATING SAID TROUGH MEMBER TO CAUSE MATERIAL CARRIED BY SAID TROUGH MEMBER TO DROP FROM ITS DISCHARGE END INTO SAID FURNACE WHEN SAID CONVEYANCE IS IN SAID UNLOADING POSITION ADJACENT SAID FURNACE. 